Design and control method of electric wheel angle module distributed type super-capacitor energy storage system

Abstract

The invention discloses a design and control method for an electric wheel angle module distributed type super-capacitor energy storage system. The design content comprises the steps of whole vehicle framework arrangement scheme design, electric wheel angle module execution system structure type selection and parameter matching, super-capacitor topological structure type selection and parameter matching, super-capacitor energy storage system electrical principle composition scheme design and control method design. According to the distributed super-capacitor energy storage system for the electric wheel angle module, a composite energy storage system of the super-capacitor and the vehicle-mounted power battery is adopted, the super-capacitor is designed in a distributed mode to form a high-integration system with the electric wheel angle module, and braking recovery energy and vibration recovery energy in the vehicle running process are stored; and nearby energy is supplied to the steer-by-wire and brake-by-wire execution system. According to the method, optimized matching of the automobile power system and the chassis system is achieved, the performance requirement of a power battery is lowered, meanwhile, a backup energy system is provided for the chassis, development of the self-energy-storage chassis technology is promoted, and the system function safety is improved.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to a design and control method of a distributed supercapacitor energy storage system for an electric wheel angle module. Background Art

[0002] With the rapid development of modern science and technology and people's increasing concern about environmental issues, the modern automobile industry is developing rapidly towards the "new four trends" of electrification, intelligence, networking and sharing. With the continuous development of intelligent electric vehicle wire-controlled chassis technology, distributed drive vehicles have begun to become an important research direction for new energy vehicles. The electric wheel angle module that replaces the traditional wheel side structure has the advantages of high integration, short transmission chain, high transmission efficiency, and rapid and accurate system response. It can realize chassis modularization and active safety control functions, which is conducive to the realization of L3 and above high-level autonomous driving technology.

[0003] In addition, in the face of frequent starting, stopping and turning in urban conditions, the on-board power battery needs to be frequently charged and discharged to meet the energy storage requirements of the braking system and steering system in the electric wheel angle module, which will cause the load condition of the on-board power battery to fluctuate and frequently charge and discharge, thereby causing the efficiency loss of the entire power system, as well as battery heating and life decay. At the same time, due to the low power density of the on-board power batteries currently on the market, in order to meet the higher peak power requirements of electric vehicles under certain specific conditions, the number of battery cells needs to be increased, resulting in high production costs for the battery system and higher requirements for chassis space layout and lightweight. Supercapacitors are energy storage components with low energy density but high power density. As a physical battery, no chemical reaction occurs inside during charging and discharging. Therefore, they have the characteristics of high charging and discharging efficiency, fast response speed, wide operating temperature range, and long working life. The number of charge and discharge times can reach more than 100,000 times, or even 200,000 times, while ordinary lithium batteries begin to decay significantly after 300-500 times. These advantages make supercapacitors more suitable as energy supply and energy storage elements for electric wheel angle modules than on-board power batteries. Therefore, the use of a composite power supply solution of supercapacitors + on-board power batteries and the highly integrated design of supercapacitors and electric wheel angle modules can save the matching cost and space occupied by on-board power batteries, simplify the wheel side structure design, and promote the modular design process of the intelligent chassis. At the same time, supercapacitors realize the self-energy storage of electric wheel angle modules. In the event of a system failure, they can be used as energy backup and serve as a redundant solution with the on-board power battery to improve vehicle driving safety.

[0004] In summary, the current automotive industry is in urgent need of a design and control method for a distributed supercapacitor energy storage system for an electric wheel angle module, so as to provide a reference for the design and control of such an energy storage system with a high degree of integration of the electric wheel angle module and the supercapacitor. Summary of the invention

[0005] The object of the present invention is to provide a design and control method for a distributed supercapacitor energy storage system of an electric wheel angle module.

[0006] To achieve the above objectives, the present invention provides a design and control method for a distributed supercapacitor energy storage system for an electric wheel angle module, comprising:

[0007] The vehicle architecture layout scheme based on the distributed supercapacitor energy storage system of the electric wheel angle module;

[0008] Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are carried out;

[0009] Based on the power requirements of the specific execution system in the electric wheel angle module and the voltage architecture of the whole vehicle, the topology structure selection and parameter matching of the super capacitor (300) are performed;

[0010] Based on the vehicle operating conditions and taking into account system failure issues, the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module are designed.

[0011] Optionally, the electric wheel angle module distributed supercapacitor energy storage system comprises: an electric wheel angle module, an on-board power battery, and an electronic control unit.

[0012] Optionally, the electric wheel angle module comprises: a first steering system (100), a drive motor (200), a super capacitor (300), a second steering system (400), a feedback suspension shock absorber (500), an electronic mechanical braking system (600), and a wheel (700);

[0013] The vehicle performance indicators include: braking distance per 100 kilometers, variable transmission ratio of the steering system, and target damping characteristic curve.

[0014] Optionally, the specific execution system comprises: a first steering system (100), an energy-feeding suspension shock absorber (500), and an electronic mechanical braking system (600);

[0015] The topological structure refers to a composite power supply topological structure between a supercapacitor (300) and an on-board power battery.

[0016] Optionally, the system failure problem includes: supercapacitor failure problem and vehicle-mounted power battery failure problem.

[0017] Optionally, based on the system composition and structural scheme of the electric wheel angle module and the vehicle performance index, the process of structural selection and parameter matching of a specific execution system in the electric wheel angle module includes:

[0018] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the electronic mechanical brake actuator motor, structural parameters of the ball screw, and structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600);

[0019] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100);

[0020] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the energy-feeding suspension shock absorber vibration reduction motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500).

[0021] Optionally, based on the power requirements of a specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle, the process of selecting a topology structure and matching parameters of the supercapacitor (300) includes:

[0022] Based on the power requirements of a specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle, a topology structure of the super capacitor (300) is selected;

[0023] Based on the power demand of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topological structure of the super capacitor (300), various parameters of the super capacitor (300) are matched and calculated.

[0024] Optionally, based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, the process of matching and calculating various performance parameters of the electronic mechanical brake execution motor, the structural parameters of the ball screw, and the structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600) comprises:

[0025] Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the electronic mechanical braking system (600) is selected;

[0026] Based on the structural scheme of the electronic mechanical braking system (600) and the performance index of the whole vehicle, determining the size of the braking gap and the time value for eliminating the braking gap;

[0027] Determining the maximum clamping force required for braking based on the structural scheme of the electronic mechanical braking system (600) and the braking distance per 100 kilometers;

[0028] Based on the size of the braking gap, the time value for eliminating the braking gap and the maximum clamping force required for the braking, the average rotation speed, the rated dynamic load and the maximum driving torque of the ball screw are determined, and the structural parameters of the ball screw are determined;

[0029] Based on the average rotation speed, maximum driving torque and structural parameters of the ball screw, the performance parameters of the electronic mechanical brake actuator motor are determined to complete the selection of the electronic mechanical brake actuator motor;

[0030] Based on the performance parameters of the electronic mechanical brake actuator motor, the structural parameters of the ball screw and the structural scheme of the reduction mechanism, the transmission ratio of the reduction mechanism and the number of teeth of each gear are determined.

[0031] Optionally, based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, the process of matching and calculating various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100) comprises:

[0032] Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the first steering system (100) is selected;

[0033] Based on the first steering system (100) structural scheme and vehicle structural parameters, determining the in-situ steering resistance torque, emergency braking torque, and return torque;

[0034] Determine the rated torque of the steering motor of the first steering system and the structural parameters of the ball screw based on the in-situ steering resistance torque, the emergency braking torque and the return torque;

[0035] Determining a rated speed of a steering motor of a first steering system based on the variable transmission ratio of the steering system and structural parameters of a ball screw;

[0036] Based on the rated torque and rated speed of the steering motor of the first steering system, the performance parameters of the steering motor of the first steering system are determined, and the selection of the steering motor of the first steering system is completed.

[0037] Optionally, based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, the process of matching and calculating various performance parameters of the energy-feeding suspension shock absorber vibration reduction motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500) comprises:

[0038] Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the energy-feeding suspension shock absorber (500) is selected, and the working requirements of the vibration reduction motor of the energy-feeding suspension shock absorber are determined;

[0039] Based on the target damping characteristic curve and the working requirements of the vibration reduction motor of the energy-feeding suspension shock absorber, the structural parameters of the ball screw, the maximum power and the maximum speed of the vibration reduction motor of the energy-feeding suspension shock absorber are determined;

[0040] Determining a base speed ratio and an overload coefficient of the vibration reduction motor of the energy-feeding suspension shock absorber based on a target damping characteristic curve and a maximum power and a maximum speed of the vibration reduction motor of the energy-feeding suspension shock absorber;

[0041] Based on the maximum power, maximum speed, base speed ratio and overload coefficient of the energy-feeding suspension shock absorber vibration-damping motor, the rated power and rated speed of the energy-feeding suspension shock absorber vibration-damping motor are determined to complete the selection of the energy-feeding suspension shock absorber vibration-damping motor.

[0042] Optionally, based on the power requirement of a specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topological structure of the supercapacitor (300), the process of matching and calculating various parameters of the supercapacitor (300) includes:

[0043] Determining the working requirements of the supercapacitor (300) based on the power requirements of the specific execution system in the electric wheel angle module and the vehicle architecture layout plan;

[0044] Based on the power demand of a specific execution system in the electric wheel angle module and the topological structure of the super capacitor (300), determining the number of super capacitors (300) connected in series and the voltage across both ends;

[0045] Based on the power requirements of a specific execution system in the electric wheel angle module and the working requirements of the super capacitor (300), the number of super capacitors (300) connected in parallel and the overall capacity are determined.

[0046] Optionally, based on the vehicle operating requirements and taking into account system failure issues, the process of designing the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module includes:

[0047] Based on the vehicle operating requirements and taking into account the system failure problem, various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module are determined;

[0048] Based on the various functional scenarios of the electric wheel angle module distributed supercapacitor energy storage system, the electrical principle composition scheme of the electric wheel angle module distributed supercapacitor energy storage system is designed;

[0049] Based on the various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module and the electrical principle composition scheme, a control method for the distributed supercapacitor energy storage system of the electric wheel angle module is designed.

[0050] The technical achievements of the present invention are:

[0051] The present invention performs structural selection and parameter matching on a specific execution system in the electric wheel angle module based on the vehicle architecture layout scheme and vehicle performance indicators of a distributed supercapacitor energy storage system of an electric wheel angle module, and performs topological structure selection and parameter matching on supercapacitors based on the power requirements of the specific execution system and the voltage architecture of the vehicle; finally, based on the vehicle operating conditions and taking into account system failure problems, the electrical principle composition scheme and control method design of the distributed supercapacitor energy storage system of the electric wheel angle module are completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0053] Figure 1 is a design flow chart in an embodiment of the present invention;

[0054] Figure 2 It is a layout diagram of the whole vehicle structure in an embodiment of the present invention;

[0055] Figure 3 is an axonometric view of an electric wheel angle module in an embodiment of the present invention;

[0056] Figure 4 is a flowchart of parameter matching in an embodiment of the present invention;

[0057] Figure 5 It is a block diagram of the electrical principle composition in an embodiment of the present invention;

[0058] Figure 6 1 is a control flow diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0059] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0060] like Figure 1 As shown, the design and control method of the electric wheel angle module distributed supercapacitor energy storage system of the present invention mainly includes the following four aspects:

[0061] ■Vehicle architecture layout scheme based on distributed supercapacitor energy storage system of electric wheel angle module;

[0062] ■Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are carried out;

[0063] ■ Based on the power requirements of the specific actuator system in the electric wheel angle module and the voltage architecture of the vehicle, the topology structure selection and parameter matching of the supercapacitor are carried out;

[0064] ■Based on the vehicle operating requirements and taking into account system failure issues, the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module are designed.

[0065] The specific details are as follows:

[0066] 1. Vehicle architecture layout scheme based on distributed supercapacitor energy storage system of electric wheel angle module:

[0067] like Figure 2 As shown, the vehicle architecture layout is mainly composed of four sets of electric wheel angle modules, on-board power batteries, and electronic control units, among which the electric wheel angle modules and supercapacitors are highly integrated. The four electric wheel angle modules of the vehicle are connected to the electronic control unit through electrical signals, and the vehicle's chassis active control functions such as driving, braking, steering, and suspension are realized under the control of the electronic control unit to meet the acceleration, deceleration, steering movement, and stable driving needs of the vehicle. At the same time, energy flow will interact between the electric wheel angle module, supercapacitor, and on-board power battery to meet the energy supply and storage functions of the vehicle.

[0068] 2. Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are carried out

[0069] Specific structure selection and parameter matching content and methods include:

[0070] (1) System composition and structural scheme based on electric wheel angle module

[0071] The system components of the electric wheel angle module include: a first steering system (100), a drive motor (200), a super capacitor (300), a second steering system (400), a feed-back suspension shock absorber (500), an electronic mechanical braking system (600) and a wheel (700). The first steering system (100), the feed-back suspension shock absorber (500) and the electronic mechanical braking system (600) constitute a specific execution system;

[0072] The structural scheme of the electric wheel angle module is as follows Figure 3As shown, the first steering system (100) is a main steering system, connected to the steering knuckle via a steering tie rod, and realizes the steering function by tie rod steering; the drive motor (200) adopts a wheel side drive form, and is connected to the hub flange of the wheel (700) via two constant velocity universal joints, and is used to provide a driving torque for the vehicle to travel; the second steering system (400) is an auxiliary steering system, connected to the chassis via a pin shaft at the top, the drive motor (200) is installed at the bottom via bolts, the first steering system (100) is installed on the side, and the energy feedback suspension shock absorber ( 500), the second steering system (400) is a redundant system of the first steering system (100), and the steering function can be realized by all-wheel steering; the energy-feeding suspension shock absorber (500) is installed on the upper cross arm, and the energy-feeding suspension shock absorber vibration reduction motor is used to provide suspension damping force to realize the vibration energy recovery function, and the specific power transmission path and working mode of the second steering system (400) and the energy-feeding suspension shock absorber (500) are relatively complicated and will not be elaborated here; the electronic mechanical braking system (600) is connected to the lug on the steering knuckle by bolts, and mainly undertakes the braking function of the vehicle.

[0073] (2) Parameter matching and selection design of distributed supercapacitor energy storage system for electric wheel angle module:

[0074] Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are performed, and based on the power demand of the specific execution system and the voltage architecture of the whole vehicle, the topology selection and parameter matching of the super capacitor (300) are performed.

[0075] The parameter matching process is as follows Figure 4 shown.

[0076] (3) Based on the composition and structural scheme of the electric wheel angle module system and the performance index of the whole vehicle, the structure selection and parameter matching of the electronic mechanical braking system (600) in the specific execution system are performed.

[0077] The selected electronic mechanical brake system (600) is mainly composed of an electronic mechanical brake actuator motor, a ball screw, a speed reduction mechanism and a brake caliper body. The electronic mechanical brake actuator motor serves as a power source, outputs a high-speed, low-torque force, and outputs a low-speed, high-torque force through the speed reduction torque increase of the speed reduction mechanism. The ball screw converts the transmitted rotational motion into axial linear motion, pushing the brake block in the brake caliper body to clamp the brake disc and complete the braking work. The parameter matching design work mainly includes the following seven aspects:

[0078] A. Determine the size of the brake gap and the time value for eliminating the brake gap:

[0079] When the automobile is in normal driving and the electronic mechanical brake system (600) is not in operation, the gap between the left and right brake pads and the brake disc is called the brake clearance. The setting of the brake clearance should not be too large, otherwise it will take too long to eliminate the clearance, making the brake response too slow. At the same time, the brake clearance should not be too small, otherwise it will easily lead to incomplete separation between the brake pad and the brake disc when the brake is released, resulting in dragging and affecting work efficiency. After determining the brake clearance, the high sensitivity requirement of the electronic mechanical brake system (600) should be considered, and a suitable brake clearance elimination time value should be designed. The brake clearance s is selected. a And the time value of eliminating brake gap t a .

[0080] B. Determine the maximum clamping force required when the electromechanical brake system (600) brakes:

[0081] According to the performance index S of the automobile braking distance per 100 kilometers 100 The maximum braking deceleration a can be calculated bmax , as shown in formula 1.1.

[0082]

[0083] in, is the braking system reaction time, u0 is the initial braking speed, that is, u0 = 100 km / h. The calculation formula of braking intensity z is shown in formula 1.2, where g is the acceleration of gravity.

[0084]

[0085] According to automobile theory, during braking, the load is transferred, and the ground normal force on the front wheel increases, which increases the front wheel adhesion limit. Therefore, the clamping force required to make the wheel (700) lock and slide is also higher. Therefore, the case of front wheel locking is selected to calculate the maximum clamping force required for the electronic mechanical brake system (600) during braking. The ground braking force F on the front wheel when the front wheel is locked is Xb1 , the front wheel adhesion limit on this road surface And the maximum front wheel brake force F μ1 The calculation formula is shown in formula 1.3-1.5.

[0086]

[0087] in, is the road adhesion coefficient, G is the gravity of the car under full load, b is the rear wheelbase, h is g is the height of the vehicle's center of mass, μ is the friction coefficient between the brake pad and the brake disc, R discis the effective friction radius of the brake disc, r is the rolling radius of the wheel (700), F max The maximum clamping force required by the electronic mechanical brake system (600) when braking. At the same time, the maximum braking force of the front wheel, the ground braking force on the front wheel when the front wheel is locked, and the front wheel adhesion limit must meet Therefore, the simultaneous equations 1.3-1.5 can be used to calculate F max .

[0088] C. Calculate the average speed of the ball screw:

[0089] According to the brake clearance s determined previously a And the time value of eliminating brake gap t a , it can be calculated that the average axial moving speed of the ball screw nut when the braking clearance is eliminated is Preliminary selection of ball screw lead L, calculation of average ball screw speed n a , as shown in formula 1.6.

[0090]

[0091] D. Check the rated dynamic load of the ball screw:

[0092] During normal driving of a car, most of the time it is in a low to medium intensity braking state. Considering the strength and size of the ball screw, two-thirds of the maximum clamping force required by the electronic mechanical brake system (600) during braking is taken as the average load Fa for the rated dynamic load C. a The verification is calculated as shown in formula 1.7-1.8.

[0093]

[0094] Among them, K h is the life coefficient, K n is the speed coefficient (the value is 1.61), K F is the load factor, K H is the hardness influence coefficient.

[0095] E. Maximum driving torque of ball screw:

[0096] After completing the verification of the rated dynamic load of the ball screw, the ball screw parameters can be selected and the various structural parameters can be determined, so as to calculate the maximum driving torque T of the ball screw. max-s , calculated as shown in formula 1.9.

[0097]

[0098] Where P1 is the ball screw lead, η p It is the positive transmission efficiency of the ball screw under preload condition.

[0099] F. Selection of electronic mechanical brake actuator motor:

[0100] In order to reduce the clamping force requirements on the driving torque of the electronic mechanical brake actuator, it is necessary to arrange a reduction mechanism to work together. The initial transmission ratio is i * , the rated speed requirement of the electronic mechanical brake actuator motor can be calculated And the continuous stall torque required to meet the maximum clamping force condition As shown in formula 1.10-1.11.

[0101]

[0102] Based on the above calculated initial values, complete the selection of motor parameters for the electronic mechanical brake and determine the performance parameters.

[0103] G. Design of speed reduction mechanism:

[0104] The mainstream reduction mechanisms include cylindrical gear pairs, planetary gear mechanisms and worm gear pairs that are mainly used with rotary motors, as well as wedge blocks and crank-connecting rod mechanisms that are mainly used with linear motors. The electronic mechanical brake actuator motor selected in the present invention is a rotary motor, so a two-stage planetary gear reducer is selected as the reduction scheme for discussion. According to the above calculation results and the various performance parameters of the selected electronic mechanical brake actuator motor, the transmission ratio i of the two-stage planetary gear reducer is determined, as shown in formulas 1.12-1.13.

[0105]

[0106] Among them, T max-d is the continuous stall torque of the motor, n e is the rated speed of the motor, Z S1 is the number of teeth of the primary sun gear, Z R1 is the number of teeth of the first gear ring, Z S2 is the number of teeth on the secondary sun gear, Z R2 is the number of teeth on the secondary ring gear, and the number of teeth on the planetary gear is Z Pi It can be calculated by formula 1.14 (i=1, 2).

[0107]

[0108] By combining 1.12-1.14, the number of teeth on each gear of the two-stage planetary gear reducer can be determined, thus completing the selection and design of the reduction mechanism scheme.

[0109] (4) Based on the composition and structural scheme of the electric wheel angle module system and the performance index of the whole vehicle, the first steering system (100) in the specific execution system is structurally selected and parameter matched.

[0110] The selected first steering system (100) adopts a rod steering method, and is mainly composed of a first steering system steering motor, a ball screw, a steering rod and a steering knuckle. The first steering system steering motor is used as a power source, and the output rotational motion is converted into axial linear motion through the ball screw, and the steering knuckle is driven to steer through the steering rod to complete the steering work. The parameter matching design work mainly includes the following two aspects:

[0111] A. First steering system steering motor torque matching:

[0112] The first steering system steering motor should mainly consider the following three torque loads in terms of steering capability: ① in-situ steering resistance torque; ② braking deviation torque of the wheel (700) around the steering kingpin generated by emergency braking, referred to as emergency braking torque; ③ return torque. At the same time, considering the dangerous working conditions of the combined action of each torque, a certain safety margin should be left for the parameter matching design of the selected steering motor.

[0113] ① In-situ steering resistance torque: In-situ steering resistance torque M s There is currently no accurate mathematical model to calculate.

[0114] The formula used more often is based on experience, as shown in Formula 2.1.

[0115]

[0116] Wherein, f is the sliding friction coefficient between the wheel (700) and the road surface; G is the total vertical load of the wheel (700), and P is the tire pressure. Since load transfer occurs during braking, the vertical force of the front wheel increases, and thus the rotation resistance torque increases, the corrected single-wheel rotation resistance torque M is ws As shown in formula 1.15, where F Xb1 and F Xb2 The ground braking forces of the front and rear wheels respectively.

[0117]

[0118] ② Emergency braking torque: When the vehicle is in emergency braking, it will generate an impact torque around the kingpin. Since electric vehicles using electric wheel angle modules do not have a steering trapezoid, they need to be offset by the output torque of the first steering system steering motor in each wheel system. The emergency braking torque M of a single electric wheel angle module wb As shown in formula 2.3, where K p The kingpin offset.

[0119]

[0120] ③ Returning torque: The return torque of the electric wheel angle module is mainly caused by the vehicle's gravity and lateral force. Considering the load transfer during braking, the return torque M wz The calculation process is shown in formula 2.4-2.6.

[0121]

[0122] M wz2 =(rsin T+e cos T)F s cos U (2.5)

[0123] M wz =M wz1 +M wz2 (2.6)

[0124] Among them, M wz1 is the gravity self-aligning moment, M wz2 is the lateral force restoring moment, U is the kingpin inclination angle, T is the kingpin caster angle, W is the average steering angle of the left and right wheels (70°), e is the tire trail, F s is the lateral force of the tire. The electric wheel angle module steering motor drives the steering rod through the ball screw, driving the steering knuckle, thereby forming a rotation torque of the wheel (700) around the z-axis. This torque must be able to meet the requirements of the sum of the in-situ steering resistance torque, emergency braking torque and return torque. The calculation process is shown in formulas 2.7-2.8.

[0125] F str L k =M ws +M wb +M wz (2.7)

[0126]

[0127] Among them, T e-str is the rated torque of the steering motor, F str is the axial force of the steering rod, L k is the vertical distance between the steering rod and the kingpin, P2 is the ball screw lead, η p is the positive transmission efficiency of the ball screw under the preload state. The matching and selection of the ball screw here is the same as above and will not be elaborated. During the vehicle steering process, as the wheel (700) changes in angle, F str and L k It will also change in real time. Therefore, the above 2.7-2.8 are mainly used for the preliminary selection of the parameters of the steering motor of the first steering system. The subsequent verification needs to establish a distributed steering system dynamics model in Adams or other motion simulation software. By analyzing the kinematic relationship between the various components during steering, the steering rod axial force Fstr The precise value of is analyzed in real time.

[0128] B. First steering system steering motor speed matching:

[0129] The rotation speed of the steering motor of the first steering system should meet the requirement of the rotation speed of the wheel (700) during steering. Meanwhile, considering that the electric wheel angle module can realize the steering system with variable transmission ratio, the rotation speed of the steering motor of the first steering system n e-str The calculation process is shown in Equations 2.9-2.11.

[0130]

[0131] v str =w p L k (2.10)

[0132]

[0133] Among them, w p is the angular velocity of the wheel (700) when turning, w w Input speed for the steering wheel angle, i w The variable transmission ratio of the steering system, v str is the axial speed of the steering rod. Similarly, v str and L k Subsequent verification also requires motion simulation software to analyze the precise values ​​of real-time changes, which will not be discussed in detail here.

[0134] Once the rated speed and rated torque of the steering motor of the first steering system are known, the parameter matching and selection of the steering motor of the first steering system can be completed to determine the performance parameters.

[0135] (5) Based on the composition and structural scheme of the electric wheel angle module system and the performance index of the whole vehicle, the structure selection and parameter matching of the energy recovery suspension shock absorber (500) in the specific execution system are performed.

[0136] The selected energy-feeding suspension shock absorber (500) is mainly composed of an energy-feeding suspension shock absorber vibration-damping motor, a ball screw and a connecting mechanism. Among them, the reciprocating linear motion of the suspension is converted into rotational motion by the ball screw, driving the energy-feeding suspension shock absorber vibration-damping motor to generate electricity and recover vibration energy. To match the parameters of the energy-feeding suspension shock absorber vibration-damping motor, it is necessary to predetermine the range of its speed and force during operation, that is, the known target damping characteristic curve. However, since the energy-feeding suspension shock absorber vibration-damping motor is in a constant power characteristic after the rated speed, the torque decreases with the increase of the speed. If the performance parameters are matched with the full speed range of the damping curve, it will lead to excessive power demand and performance waste. Therefore, the performance parameters of the energy-feeding suspension shock absorber vibration-damping motor only need to meet the working requirements of general roads. At the same time, in order to protect the energy-feeding suspension shock absorber vibration-damping motor from damage, the maximum speed needs to be designed under extreme working conditions. Its parameter matching design work mainly includes the following two aspects:

[0137] A. Energy-feeding suspension shock absorber vibration reduction motor power and speed matching:

[0138] A quarter model of the suspension is established, the target damping characteristic curve is input into the model, and the vehicle is simulated at a certain speed through each level of road surface to obtain the distribution of the relative motion speed of the energy-feeding suspension shock absorber (500) under each level of road surface. The maximum speed v in the speed distribution is selected. dam , substituting into the target damping characteristic curve to obtain the damping force F dam At this time, the working point on the curve is P, which is used as the parameter matching basis for the vibration reduction motor of the energy-feeding suspension shock absorber working on general roads. The maximum power of the vibration reduction motor of the energy-feeding suspension shock absorber is P dam As shown in formula 3.1.

[0139]

[0140] The maximum speed of the vibration reduction motor of the energy-regenerating suspension shock absorber can be matched with the maximum value of the target damping curve speed range, or the maximum speed under special circumstances specified by the national standard for the shock absorber. The calculation process is shown in Formula 3.2.

[0141]

[0142] Among them, n max-dam is the maximum speed of the vibration reduction motor of the energy-feeding suspension shock absorber, v max-dam is the relative movement speed of the energy-feeding suspension shock absorber (500) under the corresponding extreme working condition, and P3 is the lead of the ball screw in the energy-feeding suspension shock absorber (500).

[0143] B. The base speed ratio of the vibration reduction motor of the energy-feeding suspension shock absorber matches the overload coefficient:

[0144] After determining the maximum power and maximum speed of the vibration reduction motor of the energy-feeding suspension shock absorber, it is necessary to select the base speed ratio i according to the target damping characteristic curve. b and the overload coefficient λ, so that the high efficiency area of ​​the energy-feeding suspension shock absorber vibration reduction motor is distributed as much as possible in the working range of the target damping characteristic curve corresponding to the general road surface. b After the overload factor λ is calculated, the rated speed n of the vibration reduction motor of the energy-feeding suspension shock absorber can be obtained. e-dam , maximum torque T max-dam With rated torque T e-dam , as shown in formula 3.3-3.6.

[0145]

[0146]

[0147] After calculating the above parameters, the power and speed matching parameters and selection of the energy-feeding suspension shock absorber motor can be completed to determine the performance parameters.

[0148] 3. Based on the power requirements of the specific actuator system in the electric wheel angle module and the voltage architecture of the vehicle, select the topology structure and match the parameters of the supercapacitor

[0149] The supercapacitor (300) in the electric wheel angle module is mainly used to supply energy to the electronic mechanical brake actuator motor and the first steering system steering motor, and its energy source is mainly from the charging of the vehicle power battery, the braking energy recovery and the vibration energy recovery of the energy-feeding suspension shock absorber (500). At the same time, when the supercapacitor (300) has a charge state SOC sc ≤x%, the on-board power battery, the braking energy recovery and the vibration energy recovery of the energy-feeding suspension shock absorber (500) cooperate to complete the charging of the super capacitor (300), and when the super capacitor (300) has a charge state SOC sc >x%, the on-board power battery stops charging, and only the braking energy recovery and the vibration energy recovery of the energy-feeding suspension shock absorber (500) are used to charge the supercapacitor (300). The working power P of the supercapacitor (300) is sc As shown in formula 4.1.

[0150] P sc =P b +P reg-b +P reg-d -P emb -P str (4.1)

[0151] Among them, P b is the charging power of the vehicle power battery to the supercapacitor (300), and The x% can be 20-30%, P reg-b is the charging power of braking energy recovery, P reg-d is the charging power of the vibration energy recovery of the energy recovery suspension shock absorber (500), P emb The working power of the electromechanical brake actuator, P str is the working power of the steering motor of the first steering system. In the face of frequent starting and stopping in urban conditions, the supercapacitor (300) needs to undertake the work of charging and discharging at the same time. From the perspective of the internal energy of the supercapacitor (300), when P sc >0, the supercapacitor (300) is in a charging state as a whole, and when P sc <0, the supercapacitor (300) is in a discharging state as a whole.

[0152] Specific structure selection and parameter matching content and methods include:

[0153] (1) Selection of supercapacitor (300) topology:

[0154] Usually, the design of each component of the whole vehicle is carried out around the voltage architecture of the whole vehicle (usually the voltage of the on-board power battery). Based on the power demand of the supercapacitor (300) of the specific execution system in the electric wheel angle module and the voltage architecture of the whole vehicle, a fully active topology is selected as the topology between the supercapacitor (300) and the on-board power battery.

[0155] The topology is as follows Figure 5 As shown, the vehicle-mounted power battery and supercapacitor are respectively connected in series with a DC-DC converter (DC-DC1, DC-DC2), and then connected in parallel to the DC bus. This structure can realize the decoupling control of the vehicle-mounted power battery and supercapacitor, making the bus voltage more stable, while the control strategy is more flexible and more efficient.

[0156] (2) The number of supercapacitors (300) connected in series matches the voltage across both ends:

[0157] The super capacitor (300) in the electric wheel angle module is connected in parallel with the vehicle power battery using a bidirectional DC-DC converter (DC-DC). At this time, the DC-DC is used to adjust the voltage between the super capacitor (300) and the vehicle power battery. When the voltage ratio between the two approaches 1, the DC-DC efficiency is high. Therefore, when matching the parameters of the voltage across the super capacitor (300), it should be as close as possible to the vehicle power battery voltage U b The voltage across the supercapacitor (300) must not be greater than the voltage of the vehicle power battery to prevent the supercapacitor (300) from reversely charging the vehicle power battery during the vehicle driving process, thereby damaging the battery health. The calculation process of the number of supercapacitors (300) connected in series and the voltage across the supercapacitor (300) is shown in Formulas 4.2-4.4.

[0158] U uc ≤U b (4.2)

[0159]

[0160] U uc =U uc-single n sc-s (4.4)

[0161] Among them, U uc is the voltage across the supercapacitor (300), U uc-single is the nominal voltage of the supercapacitor (300) monomer, n sc-s is the number of supercapacitors (300) connected in series.

[0162] (3) Number of supercapacitors (300) connected in parallel to match overall capacity

[0163] Since the functional requirements of the supercapacitor (300) are mainly divided into two parts: the energy storage requirements for braking energy recovery and vibration energy recovery of the energy-feeding suspension shock absorber (500), and the energy supply requirements for supplying energy to the electronic mechanical brake actuator motor and the first steering system steering motor, the overall capacity requirements of the supercapacitor (300) must be considered from the two parts of ① energy storage requirements and ② energy supply requirements. The calculation process is shown below.

[0164]

[0165] E sc ≥max{E reg , E use}(4.6)

[0166]

[0167] Among them, E sc is the maximum energy that the supercapacitor (300) can provide or store, C sc is the overall capacity of the supercapacitor (300), C sc-single is the single cell capacity of supercapacitor (300), n sc-p is the number of supercapacitors (300) connected in parallel, V max and V min They are respectively the maximum voltage and the minimum voltage of the supercapacitor (300) monomer.

[0168] ① Energy storage demand E reg

[0169] The overall capacity of the designed supercapacitor (300) must be sufficient to store the energy generated by braking energy recovery and vibration energy recovery during the process of decelerating the vehicle from the highest speed to zero. The calculation process is shown in the formula.

[0170]

[0171] E reg-d =P e-dam t b (4.9)

[0172]

[0173] Among them, E reg-b is the energy generated by braking energy recovery, v max is the maximum speed of the vehicle, η reg Maximum braking energy recovery rate, E reg-d is the energy generated by vibration energy recovery, t b is the time taken by the vehicle to decelerate from maximum speed to zero. It is a safety factor to prevent energy overflow due to insufficient energy storage space of the super capacitor (300).

[0174] ②Energy demand E use

[0175] Since only when the supercapacitor (300) has a charge state SOC sc ≤x%, the on-board power battery will charge the supercapacitor (300). Considering that it takes a certain amount of time for the battery to charge the supercapacitor (300), when the energy recovery power of the drive motor (200) and the energy-feeding suspension shock absorber (500) is small due to road conditions, or the on-board power battery cannot be charged due to a fault, or the drive motor (200) and the energy-feeding suspension shock absorber (500) cannot recover energy due to a fault, it is necessary to ensure that the remaining energy in the supercapacitor (300) can meet the working requirements of the electronic mechanical braking system (600) and the first steering system (100), so that the vehicle can safely and reliably execute braking and steering commands until the vehicle stops. The calculation process is shown in the formula.

[0176]

[0177] Among them, P emb The average power of the electromechanical brake motor during the vehicle deceleration from the highest speed to zero, P str is the steering motor power of the first steering system, t stris the working time of the first steering system (100) during the braking process. By combining the above formulas, the number of series and parallel connections of the supercapacitors (300) in the electric wheel angle module, the voltage at both ends and the overall capacity can be calculated, and the parameter selection of the supercapacitor (300) can be completed.

[0178] 4. Based on the vehicle operating requirements and taking into account the system failure problem, determine the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module

[0179] (1) It has the following five functional scenarios:

[0180] Functional scenario 1: When the vehicle is in the pre-use stage, the on-board power battery only charges the supercapacitor (300) and does not supply energy to other systems. When the driver needs to use the vehicle, he will start the vehicle in advance through the mobile phone to prepare. This preparation stage is called the pre-use stage.

[0181] Functional scenario 2: Under normal circumstances, the vehicle power battery is mainly responsible for supplying energy to the drive motor (200), the second steering system steering motor and the energy-feeding suspension shock absorber damping motor. At the same time, when the supercapacitor (300) is charged to a certain state SOC sc ≤x%, the vehicle power battery charges the super capacitor (300), and when the super capacitor (300) has a charge state SOC sc >x%, the charging of the super capacitor (300) is stopped. The super capacitor (300) is mainly responsible for supplying energy to the electronic mechanical brake actuator motor and the first steering system steering motor, and at the same time stores the energy generated by the braking energy recovery and the vibration energy recovery of the energy-feeding suspension shock absorber (500).

[0182] Functional scenario 3: When the supercapacitor (300) fails, the on-board power battery stops charging the supercapacitor (300), the supercapacitor (300) stops working, and the on-board power battery is responsible for supplying energy to all systems.

[0183] Functional scenario 4: When the on-board power battery fails, the on-board power battery stops working, and the supercapacitor (300) serves as an energy backup and is responsible for supplying energy to the electronic mechanical brake actuator motor and the first steering system steering motor, so that the vehicle stops safely and smoothly.

[0184] Functional scenario 5: If the driver has finished using the vehicle and there is still energy remaining in the supercapacitor (300), the supercapacitor (300) is controlled to slowly charge the vehicle power battery at a low rate current until there is no energy remaining in the supercapacitor (300). If the supercapacitor (300) itself has no energy remaining, there is no need to charge the vehicle power battery.

[0185] (2) Specific electrical principle composition scheme:

[0186] Based on the various functional scenarios of the electric wheel angle module distributed supercapacitor energy storage system, the electrical principle composition scheme of the electric wheel angle module distributed supercapacitor energy storage system mainly consists of an on-board power battery, an on-board power battery management system (BMS), a supercapacitor, a supercapacitor management system (SCMS), a bidirectional DC-DC converter (DC-DC1, DC-DC2), a bidirectional DC-AC converter (DC-AC1, DC-AC2), a switch (S1, S2, S3), a unidirectional diode (D2, D3), an electronic control unit, an electronic mechanical brake actuator motor, a first steering system steering motor, a feed-back suspension shock absorber damping motor, a drive motor (200), and a second steering system steering motor, such as Figure 5 The working status of the electric wheel angle module distributed supercapacitor energy storage system in various functional scenarios is as follows:

[0187] Functional scenario 1: When the vehicle is in the pre-use stage, the electronic control unit transmits the working instructions of each module in the form of electrical signals through CAN communication, so that S1 is closed, DC-DC1 is in Boost mode, and DC-DC2 is in Buck mode. At this time, the motors of each system are not working, the power demand is zero, and the current will flow from the on-board power battery to the supercapacitor in one direction. The electronic control unit monitors the supercapacitor SOC in real time. When the supercapacitor charge state SOC sc When it reaches 100%, charging stops.

[0188] Functional scenario 2: Under normal circumstances, S1, S2, and S3 are always open, DC-DC1 is in Boost mode, and DC-DC2 is in alternating mode. At this time, the energy of the vehicle power battery mainly flows to the drive motor (200), the second steering system steering motor, and the energy-feeding suspension shock absorber damping motor, while the energy of the supercapacitor mainly flows to the electronic mechanical brake actuator motor and the first steering system steering motor. Since D2 and D3 limit the unidirectional flow of energy, the energy generated by braking energy recovery and vibration energy recovery will flow to the supercapacitor. When the electronic control unit monitors the SOC sc When ≤x%, S1 is closed and the vehicle power battery will charge the supercapacitor until SOC sc Stop charging when >x%.

[0189] Functional scenario 3: When a supercapacitor fails, the supercapacitor management system SCMS in the supercapacitor will send a fault signal to the electronic control unit, which will control S1 to disconnect and S2 and S3 to close. At this time, the on-board power battery will no longer charge the supercapacitor and will be responsible for supplying energy to the motors of each system. At the same time, since the closure of S2 releases the restriction of D2 on the unidirectional flow of energy, the energy generated by braking energy recovery and vibration energy recovery will flow directly back to the on-board power battery.

[0190] Functional scenario 4: When the on-board power battery fails, the battery management system BMS in the on-board power battery will send a fault signal to the electronic control unit, and the electronic control unit will control S1 to disconnect. At this time, the on-board power battery stops working and does not supply energy to any system. The remaining energy stored in the supercapacitor will be fully supplied to the electronic mechanical brake actuator motor and the first steering system steering motor, so that the vehicle can complete the necessary braking and steering work until the vehicle stops safely.

[0191] Function scenario 5: When the driver finishes using the vehicle, the supercapacitor management system SCMS sets the supercapacitor state of charge SOC sc Sent to the electronic control unit, which determines the SOC sc Is it zero? If SOC sc >0, the electronic control unit controls S1 to close, DC-DC1 is in Buck mode, DC-DC2 is in Boost mode, so that the energy in the supercapacitor slowly flows back to the vehicle power battery. If SOC sc =0, S1 is disconnected and charging stops.

[0192] (3) Based on the various functional scenarios of the electric wheel angle module distributed supercapacitor energy storage system and the electrical principle composition scheme, the specific process of the control method of the electric wheel angle module distributed supercapacitor energy storage system is as follows: Figure 6 shown.

[0193] The specific steps are as follows:

[0194] Step 0: Start;

[0195] Step 1: Determine whether the vehicle has entered the pre-start phase, if yes, go to step 2, if no, go to step 14;

[0196] Step 2: S1 is closed, S2 and S3 are disconnected, DC-DC1 is in Boost mode, DC-DC2 is in Buck mode, the vehicle power battery supplies energy to the supercapacitor in one direction, and step 3 is executed;

[0197] Step 3: Determine whether the vehicle is faulty, if yes, go to step 4, if no, go to step 7;

[0198] Step 4: Determine the cause of the fault. If it is a vehicle power battery fault, go to step 5. If it is a supercapacitor fault, go to step 6.

[0199] Step 5: S1, S2 and S3 are disconnected, DC-DC1 does not work, DC-DC2 is in alternating mode, the supercapacitor supplies energy to the electronic mechanical brake actuator motor and the first steering system steering motor, and step 11 is executed;

[0200] Step 6: S1 is disconnected, S2 and S3 are closed, DC-DC1 is in alternating mode, DC-DC2 is not working, the on-board power battery supplies energy to each system load, and step 10 is executed;

[0201] Step 7: Determine the supercapacitor state of charge SOC, if it is greater than x%, proceed to step 8, if it is greater than or equal to x%, proceed to step 9;

[0202] Step 8: S1, S2 and S3 are disconnected, DC-DC1 is in Boost mode, DC-DC2 is in alternating mode, and step 10 is executed;

[0203] Step 9: S1 is closed, S2 and S3 are disconnected, DC-DC1 is in Boost mode, DC-DC2 is in alternating mode, and step 10 is executed;

[0204] Step 10: Determine whether the vehicle is used. If yes, go to step 11; if no, go to step 3;

[0205] Step 11: Brake until the vehicle stops, and then proceed to step 12;

[0206] Step 12: Determine the supercapacitor state of charge SOC, if it is greater than 0, execute step 13, if it is equal to 0, execute step 14;

[0207] Step 13: S1 is closed, S2 and S3 are disconnected, DC-DC1 is in Buck mode, DC-DC2 is in Boost mode, and step 12 is executed;

[0208] Step 14: End.

[0209] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. Design and control method of distributed supercapacitor energy storage system for electric wheel angle module, characterized in that: The design content includes: The vehicle architecture layout scheme based on the distributed supercapacitor energy storage system of the electric wheel angle module; Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are carried out; Based on the power requirements of the specific actuator system in the electric wheel angle module and the voltage architecture of the vehicle, the topology structure selection and parameter matching of the supercapacitor are carried out; Based on the vehicle working condition requirements and considering the system failure problem, the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module are designed; The design and control method of the distributed supercapacitor energy storage system for the electric wheel angle module is also characterized in that the distributed supercapacitor energy storage system for the electric wheel angle module comprises: an electric wheel angle module, an on-board power battery, and an electronic control unit.

2. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 1 is characterized in that: The electric wheel angle module comprises: a first steering system (100), a drive motor (200), a super capacitor (300), a second steering system (400), a feed-back suspension shock absorber (500), an electronic mechanical braking system (600), and a wheel (700); wherein the first steering system (100), the feed-back suspension shock absorber (500), and the electronic mechanical braking system (600) constitute the specific execution system; The vehicle performance indicators include: braking distance per 100 kilometers, variable transmission ratio of the steering system, and target damping characteristic curve; The topological structure refers to a composite power supply topological structure between a supercapacitor (300) and an on-board power battery.

3. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 1 is characterized in that: The system failure problems include: supercapacitor failure problems and vehicle-mounted power battery failure problems.

4. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 1 is characterized in that: Based on the system composition and structural scheme of the electric wheel angle module and the vehicle performance index, the process of structural selection and parameter matching of the specific execution system in the electric wheel angle module includes: Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the electronic mechanical brake actuator motor, structural parameters of the ball screw, and structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600); Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100); Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the energy-feeding suspension shock absorber vibration reduction motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500).

5. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 1 is characterized in that: Based on the power requirements of the specific execution system in the electric wheel angle module and the voltage architecture of the whole vehicle, the process of selecting the topology structure and matching the parameters of the super capacitor (300) includes: Based on the power requirements of a specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle, a topology structure of the super capacitor (300) is selected; Based on the power demand of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topological structure of the super capacitor (300), various parameters of the super capacitor (300) are matched and calculated.

6. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 4 is characterized in that: The process of matching and calculating various performance parameters of the electronic mechanical brake execution motor, the structural parameters of the ball screw, and the structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600) based on the composition and structural scheme of the electric wheel angle module system and the performance index of the whole vehicle comprises: Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the electronic mechanical braking system (600) is selected; Based on the structural scheme of the electronic mechanical braking system (600) and the performance index of the whole vehicle, determining the size of the braking gap and the time value for eliminating the braking gap; Determining the maximum clamping force required for braking based on the structural scheme of the electronic mechanical braking system (600) and the braking distance per 100 kilometers; Based on the size of the braking gap, the time value for eliminating the braking gap and the maximum clamping force required for the braking, the average rotation speed, the rated dynamic load and the maximum driving torque of the ball screw are determined, and the structural parameters of the ball screw are determined; Based on the average rotation speed, the maximum driving torque and the structural parameters of the ball screw, the performance parameters of the electronic mechanical brake actuator motor are determined to complete the selection of the electronic mechanical brake actuator motor; Based on the performance parameters of the electronic mechanical brake actuator motor, the structural parameters of the ball screw and the structural scheme of the reduction mechanism, the transmission ratio of the reduction mechanism and the number of teeth of each gear are determined.

7. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 4 is characterized in that: The process of matching and calculating various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100) based on the electric wheel angle module system composition and structural scheme and the vehicle performance index comprises: Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the first steering system (100) is selected; Based on the first steering system (100) structural scheme and vehicle structural parameters, determining the in-situ steering resistance torque, emergency braking torque, and return torque; Determine the rated torque of the steering motor of the first steering system and the structural parameters of the ball screw based on the in-situ steering resistance torque, the emergency braking torque and the return torque; Determining a rated speed of a steering motor of a first steering system based on the variable transmission ratio of the steering system and structural parameters of a ball screw; Based on the rated torque and rated speed of the steering motor of the first steering system, the performance parameters of the steering motor of the first steering system are determined, and the selection of the steering motor of the first steering system is completed.

8. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 4 is characterized in that: The process of matching and calculating various performance parameters of the energy-feeding suspension shock absorber vibration reduction motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500) based on the electric wheel angle module system composition and structural scheme and the vehicle performance index comprises: Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the energy-feeding suspension shock absorber (500) is selected, and the working requirements of the vibration reduction motor of the energy-feeding suspension shock absorber are determined; Based on the target damping characteristic curve and the working requirements of the vibration reduction motor of the energy-feeding suspension shock absorber, the structural parameters of the ball screw, the maximum power and the maximum speed of the vibration reduction motor of the energy-feeding suspension shock absorber are determined; Determining a base speed ratio and an overload coefficient of the vibration reduction motor of the energy-feeding suspension shock absorber based on a target damping characteristic curve and a maximum power and a maximum speed of the vibration reduction motor of the energy-feeding suspension shock absorber; Based on the maximum power, maximum speed, base speed ratio and overload coefficient of the energy-feeding suspension shock absorber vibration-damping motor, the rated power and rated speed of the energy-feeding suspension shock absorber vibration-damping motor are determined to complete the selection of the energy-feeding suspension shock absorber vibration-damping motor.

9. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 5 is characterized in that: The process of matching and calculating various parameters of the supercapacitor (300) based on the power demand of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topological structure of the supercapacitor (300) comprises: Determining the working requirements of the supercapacitor (300) based on the power requirements of the specific execution system in the electric wheel angle module and the vehicle architecture layout plan; Based on the power demand of a specific execution system in the electric wheel angle module and the topological structure of the super capacitor (300), determining the number of super capacitors (300) connected in series and the voltage across both ends; Based on the power requirements of a specific execution system in the electric wheel angle module and the working requirements of the super capacitor (300), the number of super capacitors (300) connected in parallel and the overall capacity are determined.

10. The design and control method of the electric wheel angle module distributed supercapacitor energy storage system according to claim 1 is characterized in that: The process of designing the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module based on the vehicle working condition requirements and taking into account the system failure problem includes: Based on the vehicle operating requirements and taking into account the system failure problem, various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module are determined; Based on the various functional scenarios of the electric wheel angle module distributed supercapacitor energy storage system, the electrical principle composition scheme of the electric wheel angle module distributed supercapacitor energy storage system is designed; Based on the various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module and the electrical principle composition scheme, a control method for the distributed supercapacitor energy storage system of the electric wheel angle module is designed.

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